1. Field of the Invention
The present invention relates to a fine pattern forming method and a stamper.
2. Description of the Related Art
In the manufacture of semiconductors and optical recording media, a plurality of substrates having a same pattern are produced by forming a pattern on a plurality of substrates, or by transferring a pattern formed on a substrate to other substrates.
To form the pattern on the substrate, a method called photolithography is commonly used in the manufacture of semiconductors. In photolithography, a light-sensitive photoresist is used, and a pattern formed in a mask is transferred to the substrate.
The manufacture of optical recording media, however, is generally performed by forming a first mold using photolithography and subsequently plating the first mold to form a stamper. The stamper is then used for injection molding.
The patterns used in the manufacture of optical recording media have become finer in recent years. To this end, Japanese Patent Application Laid-Open No. 2005-203052 discloses a technique in which a metal oxide compound of a composition that differs from a stoichiometric composition by lacking a small amount of oxygen, known as a heat resist, is used in place of a photoresist.
Japanese Patent Application Laid-Open No. 2007-72374 discloses a nanoimprint method in which a photoresist is used, a formed substrate is used as a mold, and a pattern of the mold is transferred onto the photoresist formed on the substrate.
In conventional pattern manufacturing methods: 1) a mask, an exposure apparatus, a dry etching apparatus, and the like are required when photolithography is used; and 2) an exposure apparatus is required when a heat-resist is used.
Even when the nanoimprint method is used, the substrate having the pattern formed thereon, which forms the mold, has to be manufactured using photolithography. In the nanoimprint method, the pattern to be transferred to the substrate is first transferred to a photoresist. With the photoresist onto which the pattern has been transferred as a mask, the pattern is transferred to the substrate using a dry etching method.
A simpler method for forming the fine pattern is therefore desired.